1. Field of the Invention
The present invention relates to a storage disk turntable, a motor and a storage disk drive apparatus.
2. Description of the Related Art
In a conventional storage disk drive apparatus, a motor is provided with a turntable for holding a storage disk. The turntable includes a turntable body and a center spindle. The turntable body is made of a magnetic material. The center spindle is made of a resin integrally formed with the turntable body.
In case of a structure in which the upper and lower surfaces of the rotor yoke are covered with a resin, it is likely that deformation such as sinkage occurs on the surface of the resin member in an injection molding process. It is also likely that a weld line is generated in the portion where a resin is finally filled. In the upper outer periphery of the resin member, there is provided an outer circumferential portion which is to be fitted to the center hole of a storage disk. If the sinkage occurs or the weld line is provided in the upper portion of the resin member, it becomes impossible to manufacture a disk guide portion with increased accuracy.
In case where the turntable includes a clamping magnet, a back yoke extends into the turntable. However, there is no need to have the back yoke extend into the turntable if the clamping magnet is provided in a clamper.